1. Field of the Invention
The present invention relates to a lineographic system for entering text into cellular phones, hand-held computers, and other electronic devices.
2. Description of Related Art
Currently many wireless electronic devices use a numeric pad such as the ones on the cellular phones, or a “QWERTY” style keyboard on hand-held devices for text entering. The term “QWERTY” (pronounced /kwerti/) is the most common modern-day keyboard layout on English-language computer and typewriter keyboards. It takes its name from the first six letters seen in the keyboard's top first row of letters. The QWERTY design was patented by Christopher Sholes in 1867 and sold to Remington in 1873, when it first appeared in typewriters. Conventional QWERTY keyboards, however, require space that is not sufficiently available on smaller electronic devices, such as cellular telephones, thereby limiting the user's ability to efficiently enter text and data.
Accordingly, advancements in the field of data input have led to the development of devices that employ virtual keyboards or handwriting recognizers. However none of these modalities is satisfactory because their use is awkward, time consuming and prone to error. Several U.S. patents address these problems trying to facilitate text entry into these devices. For example, U.S. Pat. No. 5,982,303 to Smith describes an alpha-numeric method using nine (9) numeric keys arranged radially around a center point. Each character is represented by a two stroke pictographic figure resembling the printed letter. However, the strokes required to form a letter are relatively large, and the entry of numbers requires two strokes which is very cumbersome. Besides this, there is no entry for key 5 on the telephone key pad rendering this key useless. In summary, this method is too complicated for a regular user.
Published U.S. Patent Application US 2006/0066583A1 to Toutonghi et al describes a method of precise text entry using a numeric key pad comprising numeric keys and non-numeric keys. This method requires a maximum of two key presses with a minimum of lateral movement of the user's finger across the pad. However this invention requires two separate mappings, one for lower case letters and another for upper case letters which is somewhat cumbersome.
Published U.S. Patent Application US 2006/0103623A1 to Davis discloses a method and apparatus to dial a telephone number that includes at least one numeric symbol and at least one non-numeric symbol. This invention includes a touch sensitive display screen. Essentially what this method does is to convert entered non-numeric symbols to corresponding numeric symbols and has nothing much to do with entering numbers for alpha-numeric text entry.
Published U.S. Patent Application US 2006/0116135A1 to Ure describes a morphology-based text entry system for touch typing on a telephone keypad by representing each letter as a combination of two separate symbols appearing on separate keys of a keypad. The keys may be operated by using the thumbs of both hands. Input may be accelerated by pressing multiple keys at the same time. The text entry system is applicable to a variety of languages and alphabets. The main problem with this system is that it is very complicated and very difficult to memorize.
U.S. Pat. No. 6,232,892 to Burrell IV relates to a twelve button telephone keypad for alphanumeric entry. The two-key alphabetic mode requires the pressing on two quite apart push buttons that are different for upper and lower case letters.
U.S. Pat. No. 6,735,307 to Voelkers provides a device and method for selecting text from an electronic memory using a numeric telephone keypad that has at least one pressure sensor. The respective pressure value is transmitted to and processed by control electronics.
U.S. Pat. No. 6,765,556 to Kandogan et al uses two keys on a standard phone layout to reproduce a letter. Each letter requires two taps or key inputs to type in letters without looking at the keys. Depressing only a single key is needed to enter numbers. This device is programmed to recognize two-key sequences at certain letters.
U.S. Pat. No. 5,486,823 to Tsai describes a keyboard system with small number of keys allowing a single hand input operation. According to the invention a keyboard is constituted by 15 keys, and 4-bit data is sent to keyboard controller.
U.S. Pat. No. 6,885,318 to Bickerton describes a method and device for improved character input wherein the method employs a telephone keypad comprising keys able to display secondary characters such as punctuation marks. The inventor claims that this method would be particularly useful for handheld devices such as mobile radio telephones or handheld computers but the secondary characters are very limited in number.
U.S. Pat. No. 7,098,896 to Kushler et al describes a method and system of inputing alphabetic text having a virtual keyboard on a touch sensitive screen. This invention allows the writer to use the virtual keyboard, of a QWERTY layout, with a continuous contact of the touch sensitive screen. The user traces an input pattern for word by starting at or near the first letter in a decided word and then tracing through or near each letter in sequence. This invention generates a list of possible words associated with the entered part. This invention seems to be too complicated and very imprecise.
In summary, the current methods for entering text in cellular phones and other hand-held devices are difficult to operate due to the small size of the key buttons. The regular twelve button telephone keypad require up to four strokes which is very tedious and desperately slow. The handwriting recognizers are too slow and can not recognize most of the mathematical symbols.
Therefore, a good text entry system is needed to unleash the productivity of these hand held devices if we consider these remarkable statistics: More than a billion text messages a month! This is particularly surprising in view of the limited capability of the mobile key pads for text entry.